Turkish President Recep Tayyip Erdogan has expressed hope that a U.S. decision to arm Kurdish forces fighting the Islamic State extremist group in Syria will be quickly changed.
"I hope very much that this mistake will be reversed immediately," Erdogan told a news conference.
Erdogan said he wanted to believe that Turkey's allies would side with Ankara and not with "terrorist" organizations.
He vowed to bring up Turkey’s "worries" on the issue in talks with U.S. President Donald Trump on May 16 in Washington.
The comments come after the Pentagon said that Trump had given his authorization to equip the People's Protection Units (YPG) Kurdish group as it battles IS militants in Syria.
Turkey considers the YPG to be a terrorist group linked to the outlawed Kurdistan Workers Party (PKK), which has been fighting a decades-long insurgency against Turkish forces for greater autonomy.
Meanwhile, a spokesman for the U.S.-led coalition fighting Islamic State said on May 10 that the United States may start distributing some weapons and equipment to Kurdish YPG fighters in Syria "very quickly," but it will be done incrementally and be closely monitored.
"We've got a certain amount of supply in the country already that was used to equip the Syrian Arab Coalition and some of that may be distributed very quickly," coalition spokesman U.S. Air Force Colonel John Dorrian told reporters. He did not give a timeline but said it would be incremental and provided as needed.
On the ground, a U.S-backed alliance of Kurdish and Arab militias said they fully captured the town of Tabqa and Syria's largest dam from Islamic State on May 10, a major objective as they prepare an assault on IS stronghold Raqqa.
The Syrian Democratic Forces (SDF) have been battling IS for weeks in Tabqa, some 40 kilometers west of Raqqa along the Euphrates River.
Nasser Haj Mansour, an adviser to the SDF, said the town and Tabqa dam were now "completely liberated" after the SDF drove all IS fighters out of the area.
Their offensive appeared to have stalled around Tabqa, where the SDF made only slow progress after besieging the town.
They pushed into the town earlier this month, capturing most of its districts and besieging Islamic State in part of the dam.
The battle for Tabqa began after U.S. forces helped SDF fighters conduct an airborne landing on the southern bank of the Euphrates in late March.